Elastic metastructures leveraging non-uniform locally resonating systems for transmissibility enhancement

• Grant number: 19/25680-0
• Support type: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): July 01, 2020
• Effective date (End): June 30, 2021
• Field of knowledge: Engineering - Aerospace Engineering - Aerospace Structures
• Principal researcher: Vagner Candido de Sousa
• Grantee: Renan Trevizan de Melo
• Home Institution: Universidade Estadual Paulista (UNESP). Campus Experimental São João da Boa Vista. São João da Boa Vista , SP, Brazil
• Associated research grant: 18/15894-0 - Periodic structure design and optimization for enhanced vibroacoustic performance: ENVIBRO, AP.TEM

Abstract

This project is intended to modify the transmissibility characteristics of a metamaterial leveraging non-uniform tuning of locally resonating systems (resonators) associated with the main structure. Typically, the natural frequencies of the resonators are evenly tuned at a certain target frequency. As a result, the transmissibility (structural response to excitation ratio) is drastically reduced for a certain range of excitation frequencies starting at the target frequency. The width of such a frequency range (bandgap), however, strongly depends on the added mass (the more the added mass, the wider the bandgap). Therefore, the motivation for this project is to achieve configurations that lead to wider bandgaps while reducing the system mass. The results of this project are expected to support future research in which the resonators non-uniformity could be promoted by smart materials (such as piezoceramics and/or shape-memory alloys). In such a case, real time tuning of the resonators could take place as the excitation characteristics change, yielding an adaptive system.